The popularity and convenience of the Internet has resulted in the reinvention of traditional telephony services. These services are offered over a packet switched network with minimal or no cost to the users. IP (Internet Protocol) telephony, thus, have found significant success, particularly in the long distance market. In general, IP telephony, which is also referred to as Voice-over-IP (VOIP), is the conversion of voice information into data packets that are transmitted over an IP network. Users also have turned to IP telephony as a matter of convenience in that both voice and data services are accessible through a single piece of equipment, namely a personal computer. The continual integration of voice and data services further fuels this demand for IP telephony applications.
In the traditional circuit switched PSTN (public switched telephone network) environment, the forward and reverse voice paths of a telephone call between a near end station and a far end station always traverse the same set of switches and network elements. As a result, any degradation or interference in one call direction is often mirrored in the reverse direction with respect to the near end station and the far end station. For example, if a near end station hears static during the call, it is highly likely that the other party is experiencing the same problem. Accordingly, each party to the call is implicitly notified that the quality of the call is poor; as a result, the near end station may take appropriate action, such as hanging up and re-establishing the call, instead of continuing with the conservation (despite the fact that the other party may not be able to hear any of the discussion). It is recognized that such a feedback mechanism is currently lacking with respect to voice calls over the Internet.
With VOIP technology, the voice or media path between a near end station and a far end station in the forward and reverse directions are likely to be different, traversing different network elements and physical circuits with each transmission. As a result, it is entirely possible that a near end station's media packets arrive without any problems, while the far end station's media packets (in the opposite direction) may be lost or delayed. Therefore, a feedback mechanism analogous to that of the traditional telephone call over the PSTN cannot be effected. Without such notification, the near end station cannot take corrective action, such as requesting a guaranteed quality of service (QoS) on the call, or attempt to call at a later time.
Therefore, there is a need for an approach for providing notification to convey quality of a communication session.